$ { \left[\begin{array}{rr}{4} & {2} \\ {2} & {1}\end{array}\right]+\left[\begin{array}{rr}{-1} & {4} \\ {-2} & {0}\end{array}\right] = {?} } $
To find the sum of two matrices, add the corresponding items between each matrix. ${\left[\begin{array}{rr}{4}+{-1} & {2}+{4} \\ {2}+{-2} & {1}+{0}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rr}{3} & {6} \\ {0} & {1}\end{array}\right]}$